What are Appchains?
To understand Rollups-as-a-service (RaaS), we first need to establish some definitions. For the purposes of this article, we’ll assume readers have a basic understanding of L1s, sidechains, and general purpose L2 rollups (eg. Optimism and Arbitrum).
First off, what is an appchain? An application-specific blockchain, or appchain, is a blockchain dedicated to serve and operate one specific application or ecosystem instead of the countless protocols supported by public general-purpose blockchains like Ethereum. In this way, appchains offer a more sustainable long-term approach to scaling Web3 applications and products, while enabling developers to exercise greater freedom over economic structure, governance, consensus, and more for their chain.
A couple years ago, these app developers faced three primary infrastructure options when deciding where to build their on-chain ecosystem:
Public L1s or Sidechains (eg. Ethereum, Solana, and Polygon)
General-purpose L2 rollups (eg. Optimism and Arbitrum)
L1 appchain networks (eg. Cosmos)
Each of these options came with a unique set of tradeoffs that we’ll discuss below. Fortunately, rollup stacks were introduced to the landscape soon thereafter and helped bring forth a new paradigm for crypto infrastructure.
What are Rollup Stacks?
Rollup Stacks are frameworks that enable developers to build custom rollups from scratch. In practice, this enables any individual developer or team to create their own dedicated application-specific rollup (AppRollup) built on the same underlying technology as leading general purpose rollups such as Arbitrum and Optimism. As such, Arbitrum Orbit and the OP Stack represent two of the leading rollup stack providers, along with Polygon CDK and zkSync.
AppRollups built with these rollup stacks are able to combine the customizability of L1 appchains with the security, scalability, and EVM-compatibility of general purpose L2 rollups — creating a killer combination that put more power than ever into the hands of Web3 developers.
However, as with most great technologies, building AppRollups using these Rollup Stacks requires not only a comprehensive knowledge of the modular stack, but also 100s of hours of infrastructure engineering work to ensure the final rollup suits the unique needs of your team.
That’s where Rollups-as-a-Service providers like Caldera come in to help.
What are Rollups-as-a-Service (RaaS)?
Rollups-as-a-Service offer a layer of abstraction over Rollup Stacks to make it easier than ever to design, deploy, and scale performant, production-grade rollups, empowering developers to bring their grand visions into reality while leaving the difficult work to our team of experienced crypto-native engineers. At Caldera, we work to support your objective through dozens of integrations with leading infrastructure providers (ranging from Data Availability solutions to Account Abstraction providers), in addition to built-in developer tooling (eg. Bridge Interface, Block explorer) and chain-level customizations (eg. Custom Native Tokens).
RaaS vs. L1s
While deploying on top of an existing public L1 comes with strong security guarantees and robust resources, the nature of sharing blockspace with dozens of other applications inevitably hurts performance, raises user transaction costs, and limits customizability. As an L1 network and its applications grow in popularity, so do costs and processing speeds. For example, block times on Caldera chains will take 10-100 milliseconds on average compared to 10-12 seconds on Ethereum. In order to combat this scaling issue, we’ve started to see the development of more rollups, which provide sufficient scalability while still preserving the security of the underlying base chain.
RaaS providers like Caldera enable developers to leverage the security of a base layer such as Ethereum, and enjoy the customizability of a dedicated appchain, all while maintaining EVM-compatibility and access to popular developer tools.
RaaS vs. L2s
Like public L1s, every dApp deployed on top of an Ethereum L2 (including general purpose rollups like Arbitrum and Optimism) is forced to share computational resources with all the other dApps on that rollup, leading to inevitable battles for the limited blockspace. These shared networks also lack customizability in comparison to RaaS, as they’re meant to serve a wide range of usecases rather than optimize for a single one.
RaaS vs. L1 Appchains
The limited blockspace and lack of customizability mentioned above have contributed to the rise of application-specific blockchains through frameworks like the Cosmos ecosystem, Polygon Superchains, and Avalanche Subnets. But, these traditional L1 appchains require developer teams to bootstrap their own validator network and security, while possessing far smaller developer communities with fewer resources and tooling. In contrast, RaaS solutions are able to inherit security from their settlement layers, while abstracting away difficult infrastructure engineering and providing developers access to the full suite of EVM tooling.
RaaS Benefits & Tradeoffs
In summary, RaaS represents a new status quo in Web3 infrastructure, enabling developers to deploy performant, dedicated rollups in the click of a button without any of the costly and intensive research and engineering work associated.The edge in performance enables a smoother user-experience, the customizations allow for more sustainable revenue generation (through MEV optimization, sequencer fee collection, etc), while bridge interfaces and other liquidity solutions (eg. cross-chain checkout, Fiat on/off ramps, etc) are meeting users at the point of liquidity and making it easier than ever to transfer funds onto AppRollups.
